While building tf map for gmapping, how to set tf tree?
Following document,
http://wiki.ros.org/gmapping
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Subscribed Topics
tf (tf/tfMessage)Transforms necessary to relate frames for laser, base, and odometry (see below)
scan (sensor_msgs/LaserScan)Laser scans to create the map from
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I understood like as follow.
> subscribe topie as tf made it from laser , base, odom topic, and publish map topic.
> to transform tf using [ laser , base, odom ]
And in the document say like below to for making tf tree
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Required tf Transforms
→ base_linkusually a fixed value, broadcast periodically by a robot_state_publisher, or a tf static_transform_publisher.
base_link → odomusually provided by the odometry system (e.g., the driver for the mobile base)
Provided tf Transforms
map → odomthe current estimate of the robot's pose within the map frame
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Document say,
[ map → odom ]
[ base_link → odom ]
but, the project I run gmapping & built map show the tf tree like below
[ map -> odom -> base_footprint -> base_link -> base_scan ]
I can not understand what does document saying.
As I guess,
[ → base_link ] this could be changed as
[ base link -> base scan ] [ odom -> base link ] like that.
please understand me.
Thankyou.
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